| Full text | |
| Author(s): |
Procopio, Alley Michael da Silva
;
Rocha, Leandro Silva Rosa
;
Desimone, Paula Mariela
;
Giulietti, Giuliana
;
Aldao, Celso Manuel
;
Longo, Elson
;
Moura, Francisco
;
Ponce, Miguel Adolfo
Total Authors: 8
|
| Document type: | Journal article |
| Source: | MATERIALS SCIENCE AND ENGINEERING B-ADVANCED FUNCTIONAL SOLID-STATE MATERIALS; v. 292, p. 9-pg., 2023-06-01. |
| Abstract | |
The thermal treatment of CeO2 at 600 and 900 degrees C on the film response against CO is analyzed. A fluorite-type crystalline structure was observed, with the later presenting a well-defined morphology formed by the set of (100), (110) and (111) surfaces. The band-gap was 3.35 and 3.37 eV, for the 600 and 900 degrees C samples. We have proposed an equation based on the mass action law that shows the dependence of the carriers density as a function of the grain size, demonstrating that the area-volume relation can affect the number of charge carriers, which reflects in the pre-exponential A factor of conductivity. Reducing gases generate a greater number of carriers available for conduction, reflected on the A factor. When vacancies are annihilated by exposing to an oxygen atmosphere, the Ce (III) amount reduces. The activation energy and pre-factor A in air, vacuum and CO were calculated for correlating with the sample morphologies. (AU) | |
| FAPESP's process: | 13/07296-2 - CDMF - Center for the Development of Functional Materials |
| Grantee: | Elson Longo da Silva |
| Support Opportunities: | Research Grants - Research, Innovation and Dissemination Centers - RIDC |
| FAPESP's process: | 18/20590-0 - Novel renewable rare-earth based hybrid nanomaterials for environmental sensing and energy-related applications |
| Grantee: | Leandro Silva Rosa Rocha |
| Support Opportunities: | Scholarships in Brazil - Post-Doctoral |
| FAPESP's process: | 20/02352-5 - In-depth spectroscopic investigations of hybrid cerium oxide quantum-dots towards mitigation of the COVID-19 pandemic |
| Grantee: | Leandro Silva Rosa Rocha |
| Support Opportunities: | Scholarships abroad - Research Internship - Post-doctor |